JPH11212362A - Developing device - Google Patents

Abstract

(57) Abstract: A non-magnetic toner of a one-component developer can be satisfactorily charged to obtain a high-quality image, and a load on the toner when the toner is supplied to a developing sleeve or the like. And a developing device capable of realizing a low stress coating. SOLUTION: The developing device includes a rotating toner supply brush 4 which is in non-contact with the photosensitive drum 11 and the developing sleeve 1 at a position upstream of the developing section in the rotation direction of the sleeve 1.
Is installed, and a toner charging member 5 that contacts the brush 4 is installed on the upstream side in the rotation direction of the brush 4 from these opposing portions, and discharge is performed in a downstream separation region between the brush 4 and the charging member 5 by discharging. The non-magnetic toner carried on the brush 4 is charged,
The charged toner is supplied to the sleeve 1 in a non-contact manner by an electric field formed between the brush 4 and the sleeve 1.
Further, a collecting roller 9 is disposed on the downstream side of the developing unit in the rotation direction of the sleeve 1 so as to be in non-contact therewith, and the undeveloped toner on the sleeve 1 is collected in a non-contact manner by the electric field formed therebetween.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing device used for an image forming apparatus such as an electrophotographic apparatus and an electrostatic recording apparatus.

[0002]

2. Description of the Related Art Conventionally, in an image forming apparatus using an electrophotographic system, an electrostatic latent image is formed on an image carrier, developed and visualized as a toner image, and the toner image is formed on a transfer material. The image is obtained by transferring.

In general, the above-mentioned developing methods include a one-component developing method using a one-component developer composed of only a magnetic toner and a two-component developing method using a two-component developer composed of magnetic particles (magnetic carrier) and a toner. However, the one-component developing method has advantages such as a simpler construction of the developing device and easy maintenance. Currently, various one-component developing devices based on the one-component developing method have been proposed. And has been put to practical use.

A developing method using a non-magnetic one-component developing method comprising only a non-magnetic toner as disclosed in JP-A-58-116559 has been proposed. A low-cost and small-sized developing device capable of obtaining a high-quality color image has been put to practical use.

As an example, FIG. 7 shows a non-magnetic one-component developing device. In the developing device of FIG. 7, a cylindrical non-magnetic developing sleeve 1 that rotates in the direction of the arrow as a toner carrier is installed in a developing container 3 containing a non-magnetic toner of a one-component developer,
A toner supply and recovery roller 14 and a regulating blade 13 as a developer regulating member are abutted on the developing sleeve 1.

The toner supply / recovery roller 14 is formed by covering an outer peripheral surface of a core metal 14a such as SUS with an elastic member 14b such as urethane foam. The non-magnetic toner contained in the container 3 is supplied to the surface of the developing sleeve 1, and does not contribute to the development in the developing unit facing the photosensitive drum (not shown).
It has a function of scraping the non-magnetic toner returned inside from the surface of the developing sleeve 1.

The regulating blade 13 is formed by bonding an elastic member 13b such as urethane rubber to a supporting member 13a made of phosphor bronze or the like attached to the developing container 3.
3b is elastically brought into contact with the surface of the developing sleeve 1 to regulate the toner carried on the developing sleeve 1;
It is formed in a thin layer of toner and imparts triboelectric charge to the toner.

With the above arrangement, the developing device forms a thin layer of charged non-magnetic toner on the developing sleeve 1 and supplies the thin layer to the development of the electrostatic latent image formed on the surface of the photosensitive drum. And good development of the latent image became possible.

[0009]

However, in the above-described non-magnetic one-component developing device, the charge is applied to the toner by using the regulating blade 13 or the developing sleeve 1 when the toner on the developing sleeve 1 passes through the regulating blade 13. Of the layered toner on the developing sleeve 1, the toner passing near the regulating blade 13 and the vicinity of the developing sleeve 1 can be well charged. It is difficult to impart sufficient charge to the toner present inside.

For this reason, in some cases, due to regulation, the charge amount distribution of the thin toner layer formed on the developing sleeve 1 is biased, and uncharged toner and inverted toner are present in the toner layer. . The uncharged toner and the reversal toner cause image defects such as fog.

Eliminating the uncharged toner and the reversal toner,
In order to apply a predetermined charge or more to all the toners in the toner layer, the contact pressure of the regulating blade 13 with the developing sleeve 1 is increased, and the amount of the toner passing therethrough is reduced. In addition, it is necessary to increase the chance of contact with the developing sleeve 1.

However, in order to form an image having a sufficient density, a certain amount of toner is required, and there is a limit to a reduction in the thickness of the toner layer due to an increase in the contact pressure of the regulating blade 13. Further, an increase in the contact pressure of the regulating blade 13 has a problem that a mechanical load applied to the toner becomes extremely large.

Further, by rubbing the toner supply / recovery roller 14 in contact with the developing sleeve 1, new toner is supplied to the developing sleeve 1 and the remaining toner is recovered. Depending on the position of the roller 14 and the rotation direction of the roller 14, the toner remaining after development may not be completely collected.

If the remaining toner remains on the developing sleeve 1 without being collected, the remaining toner passes between the regulating blade 13 and the developing sleeve 1 again to be charged. . When the toner is excessively charged by this recharging, the adhesive force with the developing sleeve 1 increases, so that the toner is hardly detached from the developing sleeve 1 in the developing section, and is not supplied to the developing container 3 again. May be returned.

As described above, when the toner remaining on the developing sleeve 1 is constrained by its surface and passes through the supply / recovery roller 14 and the regulating blade 13 many times,
Due to the mechanical load received each time and the accumulation of heat generated at that time, the shape of the toner gradually changes, and an external additive or the like that controls the charge amount and fluidity of the toner is embedded in the toner, The toner deteriorates.

The deteriorated toner does not provide desired charging characteristics and fluidity, and causes many problems during the image forming process.

For example, when the amount of the deteriorated toner on the developing sleeve 1 increases, the supply of new toner is hindered, and the toner amount on the developing sleeve 1 after the regulation is reduced, so that the developability may be deteriorated. Further, even if the deteriorated toner is collected in the developing container 3 by the toner collecting roller and then supplied to the developing sleeve 1 again, desired charging characteristics and fluidity cannot be obtained. It cannot be obtained, and furthermore, a transfer failure such as a void is caused at the time of transfer.

Further, when the deteriorated toner is fused to the surface of the abutting portion of the regulating blade 13 and the surface of the developing sleeve 1, coating defects such as streaks occur on the toner layer on the developing sleeve 1 and the developing sleeve In order to hinder the application of charge to the newly supplied toner, the uncharged toner is transported to the developing unit, and image defects such as fog and unevenness may occur.

On the other hand, if the toner supply / collection roller 14 rubs against the developing sleeve 11 for a long time, the roller 14
Wear, damage, clogging of toner, etc. may occur, so that the role of the toner supply / recovery roller 14 may be insufficient, and good toner supply may not be possible.

As described above, the developing device using the non-magnetic toner can perform good development with a simple structure, but the durability and stability of the toner and the developing device are poor, and the toner is replenished. It is mainly used in cartridge-type developing devices that replace the entire developing device at the time of printing, but is not often used in developing devices of the type that replenishes toner whenever necessary, such as copying machines. Was.

An object of the present invention is to make it possible to form a high-quality image in which an uncharged toner does not contribute to development by developing using a non-magnetic toner of a one-component developer, and to supply a toner to a developing sleeve. Another object of the present invention is to provide a developing device that can significantly reduce the load applied to the toner when the electric charge is applied to the toner, realizes a low stress coating of the toner, and can be used as a toner replenishment type developing device for a long period of time.

[0022]

The above object is achieved by a developing apparatus according to the present invention. In summary, the present invention provides:
A developing container containing a non-magnetic one-component developer, and rotatably disposed facing an image carrier at an opening of the developing container,
A developer carrier that carries the supplied developer and conveys the developer to a developing unit facing the image carrier; and a developer carrier that is not in contact with the developer carrier on the rotation direction upstream side of the developer carrier than the developing unit. A developer supply member that is rotatably arranged and carries the developer and supplies the developer to the developer carrier; and a rotation direction upstream of the developer supply member relative to an opposing portion between the developer carrier and the developer supply member. A developer charging member disposed at one end thereof in contact with the developer supply member, and a developer support member downstream of the developing unit in the rotational direction of the developer carrier relative to a portion facing the developer supply member, and A developer regulating member disposed in contact with the developer carrying member on the upstream side in the rotation direction of the body, and a developer regulating member disposed in contact with the developer carrying member on the downstream side in the rotational direction of the developer carrying member relative to the developing section; Developer recovery member, developer carrier, developer supply member, and developer A power source for applying a voltage to each of the charging members, and the developer supply member and the developer charging member are arranged on the downstream side following the contact area with respect to the rotation direction of the developer supply member. The developer supply member is charged by discharging the developer carried on the developer supply member, and the charged developer is supplied to the developer carrier and the developer supply member. A developing device is characterized in that the developer is supplied to a developer carrier in a non-contact manner by an electric field formed by a voltage applied between members.

According to the present invention, the developer charging member comprises:
A developer charging member is formed between the developer supply member and a conductive member having a shape that forms a separation region whose distance increases toward the downstream side in the rotation direction of the developer supply member from the contact region. Has a curvature that bends to the side opposite to the developer supply section side. Particularly, the developer charging member is a roller, and the developer supply member is a brush roller. The voltage applied between the developer charging member and the developer supply member is a voltage at which an alternating electric field is formed in the separation area.

[0024]

Embodiments of the present invention will be described below in detail with reference to the drawings.

Embodiment 1 FIG. 1 is a sectional view showing an embodiment of the developing device of the present invention.

As shown in FIG. 1, the developing device of the present embodiment includes a developing container 3 containing a non-magnetic toner as a one-component developer.
A developing sleeve 1 as a developer carrier rotating in the direction of an arrow is provided in an opening of the developing container 3 facing the photosensitive drum 11, and the developing sleeve 1 is provided with a DC voltage and an AC voltage from a power source 2. Is applied. A toner supply brush 4, a toner charging member 5, and a toner regulating member (elastic blade) 8 are provided on the developing sleeve 1, and further, a toner collecting roller is provided on the inner side of the developing sleeve 1 when viewed from the opening of the developing container 3. 9 is provided with a stirring member 12 below it. A scraper 10 is in contact with the toner collecting roller 9.

The toner supply brush 4 is for supplying the non-magnetic toner contained in the developing container 3 to the developing sleeve 1.
The developing sleeve 1 is arranged at a distance of about 1 mm and is rotatable in the same direction as the rotation direction of the developing sleeve 1 (the direction in which the developing sleeve 1 moves in the opposite direction at the closest point to the developing sleeve 1). A power source 6 for applying a bias is connected to the core metal of the brush 4, and a desired voltage obtained by superimposing a DC voltage Vf on a developing bias is applied.

In the present embodiment, the toner supply brush 4 is a fur brush (brush) in which conductive fibers having a medium resistivity electrical characteristic having a volume resistivity of 10 ⁶ to 10 ⁸ Ωcm are wound around a core metal such as SUS. Roller), the planting density of the conductive fibers is 20,000 to 200,000 / inch ² , and the thickness is 1 to 10
Denier / filament, pile length 1-10 mm, nylon or rayon fiber material.

The toner charging member 5 is provided in a portion of the developing container 3 below the developing sleeve 1 so as to be in contact with the toner supply brush 4. As shown in FIG. 2, the toner charging member 5 is formed of a thin plate having a curvature that bends to the side opposite to the toner supply brush 4, and between the toner charging member 5 and the supply brush 4, On the downstream side in the rotation direction of the brush 4 following the area A, a separation area B whose distance gradually increases toward the downstream side is formed. A power supply 7 is connected to the toner charging member 5, and a desired voltage obtained by superimposing a DC voltage Vr on a developing bias is applied.

In this embodiment, as the toner charging member 5,
A metal foil of SUS or phosphor bronze having a thickness of 100 μm to 1 mm was used by being curved. The toner charging member 5 has an EPDM, NB
An elastic rubber layer of R or the like can be provided, and further, a urethane rubber layer having a resistance adjusted to 10 ⁵ Ωcm or less by dispersing carbon can be provided thereon.

The toner regulating member, that is, the elastic blade 8
Is for regulating the layer thickness of the toner applied on the developing sleeve 1, is disposed at an end of the toner charging member 5 near the brush 4, and is in elastic contact with the developing sleeve 1. In this embodiment, the elastic blade 8 has a JIS hardness of 50.
A rubber elastic body such as urethane rubber or silicone rubber having a thickness of {70} is used and is in contact with the developing sleeve 1 at a linear pressure of 5 to 50 g / cm.

The toner collecting roller 9 is electrically peeled off from the developing sleeve 1 in order to collect the developing residual toner not contributing to the development on the developing sleeve 1 into the developing container 3 and return to the developing process again. For taking and carrying,
It is arranged at a distance of about 100 μm to 1 mm from the developing sleeve 1, and is rotated in a direction opposite to the rotation direction of the developing sleeve 1 (the same direction at the closest part).

In this embodiment, a metal cylinder having a mirror-finished surface is used as the toner collecting roller 9.
In consideration of the releasability of the toner peeled off from the toner, a layer of a fluorine-based resin such as Teflon can be provided on the surface of the collection roller 9 with a thickness of about 2 μm to 50 μm. The addition of such a resin layer also has a function of preventing leakage when a very strong electric field is applied between the developing sleeve 1 and the collection roller 9.

The scraper 10 removes toner remaining after development, which is peeled off from the developing sleeve 1 and carried on the collection roller 9,
This is for scraping off the surface of the collection roller 9, and is in contact with the lower surface of the collection roller 9 so that the scraped toner falls on the stirring member 12.

The stirring member 12 rotates to supply the non-magnetic toner contained in the developing container 3 to the toner supply brush 4 while stirring.

The non-magnetic toner used in this embodiment has a weight average particle diameter of 5 μm or more obtained by mixing, dispersing, and pulverizing a colorant in a thermoplastic resin. Polystyrene and polyester resins having charging characteristics were used. The developing method is an image exposure-reversal developing method, and the photosensitive drum 1 is charged by charging means (not shown).
A voltage obtained by superposing a negative DC voltage and an AC voltage as a developing bias on the developing sleeve 1 by a power source 2 by charging the surface of the developing device 1 to a negative polarity, exposing the image by an exposing means (not shown), and forming an electrostatic latent image. Is applied so that the negative non-magnetic toner adheres to the latent image (exposed portion) (reversal development).

In this embodiment, an OPC photosensitive member is used for the photosensitive drum 11, and a coat sleeve coated with a resin in which PMMA and dimethylaminoethyl methacrylate are mixed at a ratio of 9: 1 is used for the developing sleeve 1.

The non-magnetic toner contained in the developing container 3 is conveyed to the toner supply brush 4 while being agitated by the agitating member 12, and the non-magnetic toner is transferred to the toner charging member 5 by the mechanical conveying force of the brush as the brush 4 rotates. Is transported to the contact portion.

As shown in FIG. 2, the toner supply brush 4 has a large amount of toner T between the brush fibers and an outer peripheral portion thereof.
When the toner T included in the brush 4 is modeled, it can be seen that a toner layer is formed on the conductive layer L of the brush 4 as shown in FIG. In FIG. 3, reference symbol Z denotes a distance between the toner charging member 5 and the surface of the toner layer.

The toner T carried on the toner supply brush 4 passes through the contact area A with the charging member 5 and is transported to the separation area B. Vg = Z (Vr−Vf) / (α + Z) (1) is applied due to the difference between the applied bias and the bias applied to the toner charging member 5.

Here, Vf is the DC voltage of the power supply 6 of the toner supply brush 4, Vr is the DC voltage of the power supply 7 of the toner charging member 5, and α is the supply brush 4 and the toner charging member 5.
This value is determined by the amount of the toner interposed between them and the dielectric constant.

Discharge occurs when Vg exceeds a voltage Vp defined by an approximate expression of a discharge breakdown voltage according to Paschen's law, that is, Vp = a + bZ, Z ≧ 8 μm (a and b are constants) (2) .

That is, the discharge region H is formed in the region from Z1 to Z2 (Vg> Vp) shown in FIG. In FIG. 4, Vg when Z = Z1 is a so-called discharge starting voltage Vg.
_H.

For example, Vr is -1.5 kV, Vf is -7
When the voltage is set to 00 V and the amount of toner in the brush 4 is appropriately set, a sufficient discharge is performed between the toner supply brush 4 and the toner charging member 5.

In this way, when a discharge occurs in the separation area B, ions are generated, and the generated ions adhere to the toner contained in the toner supply brush 4, so that the toner can be further charged.

Some of the negative ions among the ions generated by the discharge are attracted to the brush 4 side and adhere to the toner bound by the brush 4. Extra negative ions are absorbed by the brush 4 itself and are canceled. The positive ions generated simultaneously with the negative ions are electrically canceled on the toner charging member 5 side.

Since new toner is sequentially supplied to the toner supply brush 4 from the inside of the developing container 3 by the stirring member 12, the brush 4 side does not charge up. In the discharge area, that is, in the separation area B, the toner is always supplied. Discharge is repeated. In the contact area A between the toner supply brush 4 and the toner charging member 5, since the brush 4 and the metal constituting the charging member 5 are in contact with each other, the contact area A is applied to the toner T interposed between the brush 4 and the charging member 5. The load is extremely low.

As described above, the toner T contained in the supply brush 4 is frictionally charged by the brush 4 coming into contact with the brush fibers and adhered to the ion by the discharge in the separation area B.
After the appropriate amount of charge is applied, the toner is conveyed to the closest portion between the developing sleeve 1 and the brush 4 downstream of the separation area B in the rotation direction of the brush 4. In the closest part, the toner is drawn from the supply brush 4 to the surface of the developing sleeve 1 and supplied to the developing sleeve 1 by a potential difference corresponding to a DC voltage between the bias applied to the developing sleeve 1 and the bias applied to the brush 4. .

For example, the DC component V of the toner supply brush 4
DC component of development bias = -35 for f = -700V
When the voltage is set to 0 V, the behavior of the negatively charged toner flies from the toner supply brush 4 to the developing sleeve 1 by the action of the electric field due to the difference of −350 V. Of course, this applied voltage depends on the type of toner, the distance between the brush 4 and the developing sleeve 1, and the
And the peripheral speed of the developing sleeve 1. These various amounts are determined so that a desired amount of toner having an appropriate charge amount can be supplied.

The toner supplied onto the developing sleeve 1 is
The toner image is carried on the surface by a mirror force, is conveyed to the elastic blade 8 of the toner regulating member, and is regulated again by the elastic blade 8 so as to form a thin and dense toner layer having a more uniform charge amount distribution.

In the present invention, since the toner is sufficiently charged in advance and then supplied to the developing sleeve 1 in a non-contact manner, the mechanical stress on the toner is significantly reduced as compared with the conventional supply method. In addition to this, only a sufficiently charged toner can be supplied onto the developing sleeve 1, so that there is almost no reversal component in the charge amount distribution in the toner layer, and a high-quality image free of fog or the like can be obtained. Will be possible.

The toner that has passed through the elastic blade 8 is transferred and developed according to the electrostatic latent image on the photosensitive drum 1 at a portion facing the photosensitive drum 11, and the obtained toner image is formed on the photosensitive drum 1. With rotation, the sheet is conveyed to a transfer unit (not shown), where it is transferred onto a transfer material such as paper.

On the other hand, without contributing to the development, the developing sleeve 1
The toner that has been returned to the inside of the developing container 15 while being carried thereon is peeled off from the developing sleeve 1 by a strong electric field formed at the closest portion between the collecting roller 9 and the developing sleeve 1,
It is carried on the surface of the collection roller 9 and collected. The carried toner is scraped off by a scraper 10 arranged so as to be in contact with the surface of the collection roller 9 and is returned to the development process again.

As described above, by using the rotating cylindrical roller 9 as the developer collecting member, the fresh electrode surface always faces the surface of the developing sleeve 1, and a stable electric field is always generated between the developing sleeve 1 and the developing roller 1. Since the toner is formed between the rollers 9, the collection efficiency of the toner from the developing sleeve 1 is almost 100%.

Embodiment 2 FIG. 5 is a sectional view showing another embodiment of the developing device of the present invention.

The toner charging member used in the present invention is not limited to the plate-shaped charging member 8 shown in FIG. 1 of the first embodiment. For example, as shown in FIG. Even if used, the same or higher effects can be obtained.

In the toner charging member 8 of the first embodiment, there are not a few cases where the reverse toner or the like adheres to the surface facing the separation region B formed between the toner charging member 8 and the toner supply brush 4 to hinder discharge.

Therefore, in this embodiment, a roller-shaped charging member, that is, a charging roller 15 is brought into contact with the toner supply brush 4 and is used by rotating it as shown by the arrow in the figure. The scraper 16 was arranged so as to be in contact with the scraper 16 so as to scrape off the toner adhering to the surface.

In this embodiment, a metal cylinder is used as the charging roller 15. However, similarly to the charging member 8 of the first embodiment, an elastic rubber layer such as EPDM or NBR rubber is provided on the surface of the charging roller 15, and furthermore, A urethane rubber layer in which carbon is dispersed can be provided on the peripheral surface.

According to the present embodiment, the charging roller 15 is used as the toner charging member, and the scraper 16 is brought into contact with the surface of the charging roller 15. And dirt on the surface forming the separation region (that is, the discharge surface),
Charging can be always applied to the toner by a stable discharge.

Accordingly, similarly to the first embodiment, the mechanical stress on the toner can be remarkably reduced, and only a sufficiently charged toner can be more stably supplied onto the developing sleeve 1 to further improve the quality. Images can be obtained.

Embodiment 3 FIG. 6 is a sectional view showing still another embodiment of the developing device of the present invention.

In this embodiment, as shown in FIG. 6, the power supply 6 of the toner supply brush 4 applies a DC voltage Vf to the supply brush 4.
The feature is that only the voltage is applied.

In the first embodiment, a voltage obtained by superimposing an AC voltage and a DC voltage is applied to the supply brush 4 by the power supply 6. However, when only the DC voltage Vf is applied as in the present embodiment, the voltage is the same as that of the first embodiment or More effects can be obtained.

For example, when a voltage obtained by superimposing a DC voltage of -350 V on an AC voltage having a peak-to-peak voltage Vpp = 1.8 kV and a frequency f = 2.0 kHz is used as a developing bias, the power supply 7 applies the voltage to the charging member 5. Assuming that the DC voltage Vr to be applied is -1.5 kV, the charging member 5 has Vpp = 1.8
A voltage obtained by superimposing a DC voltage of -1.85 kV on an AC voltage of kV, f = 2.0 kHz is applied. Therefore, if only the DC voltage Vf = −700 V is applied to the supply brush 4, an alternating electric field is formed in the separation area B.

As described above, in this embodiment, since the AC electric field is formed in the separation area B, the discharge in the separation area B can be more stabilized, and the toner can be charged more uniformly and without unevenness. .

[0067]

As described above, according to the present invention,
Without using a contact-type developer supply member conventionally used in a non-magnetic one-component development method, only a non-contact and sufficiently charged toner can be supplied to a developer carrier, and as a result, In addition, it is possible to eliminate the bias of the charge amount distribution in the toner layer formed on the developer carrying member,
Non-uniformity or scattering at the time of transfer was reduced, and an image of good quality could be obtained.

Further, since the toner is supplied and collected in a non-contact manner for each rotation of the developer carrier, the load on the toner is reduced, and the life of the toner is greatly improved.
The life of the developing device itself can be extended, and the developing device can be used in a developing device of a type in which a developer installed in a copying machine or the like is supplied. Furthermore, since there is no development history in the toner layer coated on the developer carrier, there is no ghost of the image, and it is possible to obtain a high-quality image on the surface.

[Brief description of the drawings]

FIG. 1 is a sectional view showing one embodiment of a developing device of the present invention.

FIG. 2 is a detailed view showing a developer supply unit in the developing device of FIG.

FIG. 3 is an explanatory diagram illustrating a discharge region in the developer supply unit of FIG. 2;

FIG. 4 is an explanatory diagram showing discharge conditions in a discharge region of FIG. 3;

FIG. 5 is a sectional view showing another embodiment of the developing device of the present invention.

FIG. 6 is a sectional view showing still another embodiment of the developing device of the present invention.

FIG. 7 is a cross-sectional view illustrating a conventional developing device.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 developing sleeve 2 developing bias power supply 3 developing container 4 toner supply brush 5 toner charging member 6 toner supply brush power supply 7 toner charging member power supply 8 toner regulating member (elastic blade) 9 toner collection roller 10 scraper 11 photosensitive drum

Claims (6)

[Claims] A developing container containing a non-magnetic one-component developer; and an image carrier which is rotatably disposed at an opening of the developing container so as to face the image carrier and carries the supplied developer. A developer carrying member that conveys the developer to the developing unit opposed to the developing unit, and is arranged in a non-contact and rotatable manner with the developer carrying member upstream of the developing unit in the rotation direction of the developer carrying unit, and carries the developer. A developer supply member that supplies the developer to the developer carrier, and one end of the developer supply member that is in contact with the developer supply member on the upstream side in the rotation direction of the developer supply member from an opposing portion between the developer carrier and the developer supply member. A developer-carrying member, a developer-carrying member disposed downstream of the portion facing the developer-supplying member in the rotational direction of the developer-carrying member and upstream of the developing portion in the rotational direction of the developer-carrying member; A developer regulating member disposed in contact with the developer, the developer carrying member being more than the developing unit; A developer collecting member disposed in non-contact with the developer carrying member on the downstream side in the rotation direction of the body, and a power source for applying a voltage to each of the developer carrying member, the developer supply member, and the developer charging member; The developer supply member and the developer charging member, with respect to the rotation direction of the developer supply member, has a separation region in a downstream portion following the contact region, in the separation region, The developer carried on the developer supply member is charged by discharging, and the charged developer is charged by an electric field formed by a voltage applied between the developer carrier and the developer supply member. And supplying the developer to the developer carrier in a non-contact manner. 2. The developer charging member has a shape in which a distance region is formed between the developer charging member and the developer material supply member, the distance region extending toward the downstream side in the rotation direction of the developer supply member from the contact region. 2. The developing device according to claim 1, comprising a conductive member. 3. The developing device according to claim 2, wherein the developer charging member has a curvature that is bent to a side opposite to a side of the developer supply section. 4. The developing device according to claim 3, wherein said developer charging member is a roller. 5. The developing device according to claim 1, wherein said developer supply member is a brush roller. 6. The method according to claim 1, wherein the voltage applied between the developer charging member and the developer supply member is a voltage at which an alternating electric field is formed in the separation region. Developing device.